Transcript for North Korea Cuts Economic Joint Venture With South Korea

drones and disable speedboats. We head to the korean peninsula rks the region on a hair trigger tonight. The young leader talks of war. He raised the stakes higher today. Abc's bob woodruff is on the ground for us in seoul. Reporter: North korea announced through state television today it's withdrawing more than 50,000 workers from a joint korean industrial park, cutting its last economic ties to the south. It comes as the world waits to see if the north attpts another missile test this week. The people throughout korea have not experienced war for more than 60 years now. But for the very first time, north korea has a leader who has no memories whatsoever of those battle, which make him even more unpredictable. He's only been in power for a year and a half. Across the border, he'sacing another untested leader. Newly leaked park geun-hye. Her past is tragic, her mother killed by a north korean sympathizer. Her father, who was also once president, murdered by his own intelligence chief. The question, how will she act if north korea's leader pushes her to the drink? Bob woodruff, abc news, seoul.

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